Simple DIY 3x4 LED display for Arduino MEGA / Uno / Nano

In this Instructable I’ll show you how to make a small 3x4 LED ‘display’ for an Arduino with a minimum of 12 pins (in this case I used an Arduino Uno). One reason for me to build this was to make a small display by just using the Arduino without needing an extra microcontroller - I just wanted to build something with with basic components. I know that I could do this better but it was my first own Arduino project (before that I just re-build other projects and copied the codes).”